No evidence that nuclear weapons deterred

R D DON states that he believes that "our deterrent has protected us and kept the peace for the past 50 years" (June 24). Why? This is not a belief I share, for the simple reason that he can offer no proof of this. The theory of deterrence is essentially flawed because there is no way of demonstrating that it has worked. There is absolutely no evidence to support the view that if we had not possessed the nuclear deterrent we would have been invaded, attacked or in any other way violated as a nation state.

You cannot make a causal connection between our ownership of a small nuclear resource and the fact that there has been peace. What evidence is there to support the view that Russia would have trampled all over us if we had not possessed a bomb? It is very inviting to postulate such a causal connection but there is none. That is the problem with a theory of deterrence. It used to be said that capital punishment was a "deterrent" - but how do you know? How many people were out there wanting to murder their wife/husband /lover, etc, but did not because of capital punishment? You simply do not know - all you do know is that it did not deter a certain number and they went ahead and committed murder anyway. Oddly enough, after capital punishment was abolished in the late 1960s the number of murders in Britain actually went down.

That there has been "peace" (well, apart from the Falklands, the Balkans, Afghanistan, Iraq, Chechnya, etc) and that we have happened to own a little handful of nuclear weapons are in no demonstrable way connected. That is an opinion. And there is no evidence that Russia (or America) ever had any intention of invading us after 1945. Our possession of nuclear weapons was an irrelevance to their foreign policy.

There may be reasons for our retention of nuclear weapons (although personally I can think of none), but the concept of deterrence is most certainly not one of them. It is an illusory self-deception.